This study analyzes how the use of applets promotes the perception of Mathematics Self-Efficacy in elementary school students. The study was applied to a second-grade class of 24 participants (11 female and 13 male, aged between seven and eight) from a primary school in Portugal. The data collected through validated questionnaires was used to analyze the students’ perception of Mathematics Self-Efficacy. The intervention phase took place over five sessions. During the sessions, the students solved tasks in an applet to understand the meanings of the arithmetic operation of multiplication. The five sessions were structured based on the Exploratory Teaching model, which structures a lesson in four phases2, 3. The results show that using the applet through Exploratory Teaching had statistically significant results on the students’ Mathematics Self-Efficacy. After the intervention, the students were mainly able to solve arithmetic operations, use drawing or schematics, perform multiplications by adding equal parts, calculate the product between natural numbers, solve problems involving multiplicative situations, solve numerical problems, and solve mathematical problems.